Physics Bucharest 2017

Test 2: Dose rate and gantry speed

 Dose [MU] = dose rate [MU/min] *arc length [ o ] *(1 / gantry speed) [s/ o ] * 1/60 [min/s]

 Dose rate  Arc length

105 MU/min 210 MU/min

600MU/min

82.5 o 4.8 o /s

41.25 o 4.8 o /s

13.3 o 4.4 o /s

 G speed

Image should be homogeneous

1/60 min/s

1/60 min/s

1/60 min/s

 Dose

= 30 MU

= 30 MU

= 30 MU

C. Clifton Ling, Pengpeng Zhang, Yves Archambault, Jiri Bocanek, Grace Tang, M. Phil, and Thomas Losasso, Commissioning And Quality Assurance Of Rapidarc Radiotherapy Delivery System Int. J. Radiation Oncology Biol. Phys., Vol. 72, No. 2, Pp. 575–581, 2008